Adds 8.04 oz. for an inertia mass of 5.76 kg-cm2This complete flywheel assembly features an increase in inertia mass that smoothes the power delivery. Helps get power to the ground and keep your momentum up through corners and tricky sections. Easy to install allowing you the opportunity to change flywheels for different types of riding. NOTE：Flywheels are measured by inertia weights because the affect of the weight differs depending on where it is in relation to the center of the crank. A 4 oz. and 6 oz. weight might have the same affect depending on where they are positioned in relation to the center of the crank.